Jesse Barrett "Oley" Oldendorf (16 February 1887 – 27 April 1974) was an admiral in the United States Navy, famous for defeating a Japanese force in the Battle of Leyte Gulf during World War II. He also served as commander of the American naval forces during the early phase of the Battle of the Caribbean. In early 1942, a secret group of senior Navy officers empaneled by President Franklin D Roosevelt assessed him as one the 40 most competent of the 120 flag officers in the Navy.